The present invention relates to a telescoping tube assembly. In particular, the present invention relates to a telescoping tube assembly that includes a cabling system.
Telescoping tube assemblies such as disclosed in U.S. Pat. Nos. 5,465,854 and 6,026,970 are known. Generally, the telescoping tube assemblies disclosed in these patents include a first longitudinal tube section attached to a mounting platform and a second longitudinal tube section that telescopes relative to the first longitudinal tube section. Additional longitudinal tube sections can be disposed within the each other and within the second longitudinal tube section.
Generally, any cabling that is necessary for conducting a desired operation has been disposed on the exterior of the longitudinal tube sections. As the longitudinal tube sections extend and retract, the cabling has extended and retracted on the exterior along with the longitudinal tube sections.
In some applications, the telescoping tube assemblies are used to conduct underwater operations. A tool head with a cutting tool, for example, can be mounted on the remote end of the innermost longitudinal tube section. The longitudinal tube sections and cabling associated with the longitudinal tube sections extend into a water tank to carry out the desired operation.
The cutting tool, for example, can be used to cut metal in a radioactive water tank of a nuclear plant. Although the telescoping tube assemblies described above can be used to position the cutting tool within the tank, the existing cabling system is inadequate. In particular, the existing cabling system includes a cable housing with many crevices. The crevices can retain radioactive water as the tube assembly is retracted from the tank, which complicates decontamination. Inadequate decontamination can be hazardous due to contamination of other equipment and/or exposure of personnel to radioactivity.
The cabling that is necessary to traverse the longitudinal tube sections in the extended position can be quite long. When the telescoping assembly is in the retracted position, an undesirably large amount of cabling may be compressed into a small area that can lead to problems with tangling.
In a first aspect, the invention pertains to a telescoping tube assembly that includes a frame and a first longitudinal tube section mounted on the frame. A second longitudinal tube section is disposed within the first longitudinal tube section and adapted for telescoping motion into and out of the first longitudinal tube section. The telescoping tube assembly also includes a cabling system that includes a top pulley assembly and a bottom pulley assembly, the bottom pulley assembly adapted for movement in response to the telescoping motion of the second longitudinal tube section. One or more cables extend within the telescoping tube assembly from the remote end of the innermost longitudinal tube section and traverse the top pulley assembly, the bottom pulley assembly and are fixed relative to the frame.
In another aspect, the invention pertains to a telescoping assembly including a frame and a plurality of nested longitudinal tube sections wherein the outermost longitudinal tube section is fixed relative to the other, inner longitudinal tube sections. The telescoping tube assembly also includes a cabling system that includes a top pulley assembly and a bottom pulley assembly wherein the bottom pulley assembly is adapted for movement in response to the telescoping motion of the second longitudinal tube section. One or more cables extend within the telescoping tube assembly from the remote end of the innermost longitudinal tube section and traverse the top pulley, the bottom pulley and are fixed relative to the frame. A linear guide is attached to the frame and constrained to provide linear motion to the bottom pulley assembly in response to the telescoping motion of the longitudinal tube sections.